Ultra low power dual quantizer architecture for oversampling delta-sigma modulator

Abstract

Power consumption of analog-to-digital converters (ADCs) is one important requirement for automotive and consumer devices. One flavor of an ADC is a dual quantizer architecture for oversampling delta-sigma modulators. The dual quantizer delta-sigma modulator has a first quantizer for digitizing the output of the loop filter and a second quantizer for digitizing the input of the quantizer. However, the quantization noise of the second quantizer is a highly correlated signal and significantly degrades the spectrum of the delta-sigma modulator. To address this issue, an improvement to the dual quantizer architecture is made to cancel the quantization noise of the second quantizer that is digitizing the input. Furthermore, the improvement allows the second quantizer to run at a much slower sampling rate than the first quantizer. Advantageously, the improvement provides reduction in power consumption and the overall area of modulator.

Description

TECHNICAL FIELD OF THE DISCLOSURE[0001]The present invention relates to the field of integrated circuits, in particular to a low power dual quantizer architecture for oversampling delta-sigma modulators.BACKGROUND[0002]In many electronics applications, an analog input signal is converted to a digital output signal (e.g., for further digital signal processing). For instance, in precision measurement systems, electronics are provided with one or more sensors to make measurements, and these sensors may generate an analog signal. The analog signal would then be provided to an analog-to-digital converter (ADC) as input to generate a digital output signal for further processing. In another instance, an antenna generates an analog signal based on the electromagnetic waves carrying information / signals in the air. The analog signal generated by the antenna is then provided as input to an ADC to generate a digital output signal for further processing.[0003]ADCs can be found in many places suc...

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